Drones have garnered significant attention across various industries, including agriculture, logistics and inspection, due to their ability to operate in confined or elevated spaces that are inaccessible to human workers. However, drones flying in indoor spaces present unique challenges, particularly the risk of collisions with walls and obstacles that can lead to crashes. To address this issue, this study focuses on the development of a protective guard designed to enclose the entire drone, thereby preventing contact with obstacles and reducing crash risks. The guard is constructed using lightweight and durable Carbon Fiber Reinforced Plastics (CFRP) material, specifically employing thin and flexible CFRP flat bars. The spherical shape of the guard ensures that the drone can maintain flight regardless of the direction of impact, providing omnidirectional protection. Additionally, the design incorporates a low center of gravity, which allows the drone to automatically return to its original orientation for taking off again if it falls. This mechanism enhances the stability and resilience of the drone in indoor environments. The effectiveness of the guard was evaluated through a series of tests, demonstrating its ability to protect the drone during flight, even with light contact with objects.